Rearrange the equation so $q$ is the independent variable. $-7q+12r=3q-4r$ $r=$
To arrive at a correct equation, we have to solve the equation for $r$. $\begin{aligned}-7q+12r&=3q-4r\\\\ 16r&=10q\\\\ r&=\dfrac{10q}{16}\\\\ r&=\dfrac{5}{8}q\end{aligned}$ The following equation is rearranged so $q$ is the independent variable: $r=\dfrac{5}{8}q$